<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<select>
	<option name="sex"></option>
	<option th:selected="1 == ${sex}">男</option>
	<option th:selected="0 == ${sex}">女</option>
</select>
</body>
</html>